Telephone



(No Model.)

' E. H. LYON.

A TELEPHONE. I No 416,476. Patented Dec. 3, 18 89.

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UNITED STATES PATENT OFFICE.

EDWARD H. LYON, OF NEEDI-IAIWI, MASSACHUSETTS.

TELEPHONE.

SPECIFICATION forming part of Letters Patent No. 416,476, dated December 3, 1889.

Application filed September 23, 1889- Serial No. 324,748. (No model.)

To all whom it may concern:

'Be it known that I, EDWARD H. LYoN, of Needham, in the State of Massachusetts, have inventeda new and useful Improvement in Telephones, of which the following is a specification.

The invention relates to a class of telephonetransmitters in which a finely-divided conducting material is employed as the circuitvarying medium. As in some telephones of that class heretofore invented by others the finely-divided conducting material lies between two electrodes, to both of which the vibrations of the diaphragm are communicated, to the front or working-electrode directly, but to the back or weighted electrode through the working-electrode and the finelydivided conducting material; and as in some other telephones, also not of my invention, the two electrodes have a common movable frame pressing toward the diaphragm and are kept apart within such frame by a spring, which has the etfect of making the workingelectrode follow the vibrations of. the diaphragm more rapidly than the back electrode. In these instruments the volume of sound is dependent upon the amplitude of mot-ion of the working-electrode relatively to the other, or, in other words, upon the amplitude of variations in the distance between the two electrodes, and clearness of articulation is dependent upon the freedom of motion of the sound-receiving diaphragm and the accuracy with which the working-electrode follows the vibrations of the sound-receiving diaphragm.

The objectof this invention is to increase the amplitude of motion of the working-electrode and reduce the load or restraint upon the diaphragm to a minimum. This I have accomplished by enormously increasing the weight or inertia of the back electrode, whereby substantially the whole of the movement of the diaphragm is absorbed by the working-electrode, and pivoting the common support or frame of the electrodes from beneath in such manner that it is nearly in a position of equilibrium and offers ,a diminishing resistance to the diaphragm as the diaphragm vibrates toward it.

In the drawings, Figure l is a sectional elevation of a telephone-transmitter embodying my invention. Fig. 2 is a rear elevation of the same.

D is the diaphragm. E is the front electrode; B, the back electrode; P, the finelydivided conducting material, all within a heavy frame F, consisting of two metallic ring-disks a a, with a separating ring-disk a, of insulating material, bolted together by bolts b, insulated from ring-disk a by proper bushing, as shown. The said heavy frame F, carrying the said several operative parts, is pivoted at t to a standard S, as shown. The front electrode E is a disk of carbon soldered to a disk of metal m, working freely within said frame F and carrying apin p, which presses lightly against the diaphragm D. The back electrode B is a disk of carbon soldered to the screw-plug G. A ring 6, of elastic non-conducting material, tends to force the electrodes E and B apart, and serves as the sides of the containing chamber for the finely-divided conducting material. The heavy frame F adds greatly to the inertia of the back electrode B; but the whole mass, including frame and operative parts supported by it, presses lightly against the diaphragm, being pivoted nearly in a position of equipoise, as stated above.

I claim The combination, with the diaphragm, of the heavy frame pivoted from beneath carrying the two electrodes, the finely-divided conducting material, and the spring tending to separate said. electrodes, substantially as described.

. EDlVARD I-I. LYON.

WVitnesses:

HAMMOND V. HAYES, ANTHONY 0. WHITE. 

